RadioShack hoped PC sales would offset the income decline caused by waning interest in CB radios

Photo: Computer History Museum
Borrowed Peripherals: The original TRS-80 came with 4K of RAM and a mass storage system that was, essentially, a RadioShack cassette player. The monitor was an RCA black-and-white television set with minor modifications.

There are people alive today who remember a time when a single retailer could dominate an entire product category. There was Thom McAn in shoes. F.W. Woolworth in inexpensive clothing. Tower Records in primitive music storage media. And once upon a time a company called RadioShack parlayed preeminence in do-it-yourself electronics into a surprisingly long-lived dominant position in home computers.

Early on, the market for PCs depended upon hobbyists. Several home computers were sold as kits (the Altair 8800 being by far the best known), and Apple was hardly the only early PC maker to start in a garage.

Given RadioShack’s role in the DIY electronics space, the company was obliged to consider getting into personal computers, but it balked at first. It wasn’t clear the market would grow much. Furthermore, if RadioShack did start selling home computers, they would be among the most expensive things the company sold, by a lot. But in the latter half of the 1970s, demand began waning for the citizens band radio, its top-selling item, and the company needed a new hit product. Tandy, RadioShack’s parent company, decided to take its chances with PCs.

Tandy/RadioShack (TRS) built its TRS-80 Model 1 around Zilog’s 1.77-megahertz Z80 microprocessor (hence the “80” in TRS-80). The Z80 had been introduced in 1976, and at US $25 a pop it was the cheapest of the high-performing microprocessors available. That low cost meshed well with the company’s desire to keep the price of the final product as low as possible. [See “Chip Hall of Fame: Zilog Z80 Microprocessor,” IEEE Spectrum, June 2017.]

Photo: Computer History Museum
Teacher’s Pet: RadioShack made educational software available for the original TRS-80, part of a successful strategy to crack the school market.

The keyboard was built into the top of the computer’s main circuit board (the typical configuration in those days), and the monitor was essentially a 12-inch black-and-white CRT TV screen. Floppy-disk readers had been invented, but they were still expensive, so Tandy’s choice for a data storage device for the TRS-80 Model 1 was a RadioShack cassette tape player/recorder.

Two other PCs introduced in 1977 that sold reasonably well were the Apple II and the Commodore PET 2001; they were priced at $1,298 and $795, respectively. The TRS-80 Model 1 base system, including the monitor, was priced at $599.

Despite some justifiable consumer complaints of low quality, Tandy/RadioShack’s TRS-80 Model 1 found a huge market and helped PCs evolve from a hobbyist curiosity to a mass-market commodity. In retrospect, Tandy made adept use of an advantage it had over almost all other computer makers at the time: the vast, and international, distribution network of its RadioShack stores. RadioShack was the biggest retailer of PCs through 1982, at which point its TRS-80 line began to be eclipsed by more powerful and versatile machines, including IBM’s Personal Computer, various IBM PC-compatibles, and Apple’s Macintosh line.

Even though its own line of PCs faded, Tandy would remain the biggest personal computer manufacturer in the world through the early 1990s, building computers for other companies, such as AST Research, Digital Equipment Corp., GRiD Systems Corp., Olivetti, and Panasonic.